This part of IEC 60079 explains the potential ignition hazard from equipment using optical
radiation intended for use in explosive gas atmospheres. It also covers equipment, which
itself is located outside but its emitted optical radiation enters such atmospheres. It describes
precautions and requirements to be taken when using optical radiation transmitting equipment
in explosive gas atmospheres. It also outlines a test method, which can be used to verify a
beam is not ignition capable under selected test conditions, if the optical limit values cannot
be guaranteed by assessment or beam strength measurement.
This standard contains requirements for optical radiation in the wavelength range from
380 nm to 10 μm. It covers the following ignition mechanisms:
optical radiation is absorbed by surfaces or particles, causing them to heat up and, under
certain circumstances, this may allow them to attain a temperature which will ignite a
surrounding explosive atmosphere;
direct laser induced breakdown of the gas at the focus of a strong beam, producing
plasma and a shock wave both eventually acting as the ignition source. These processes
can be supported by a solid material close to the breakdown point.
This standard does not cover ignition by ultraviolet radiation and by absorption of the radiation
in the explosive mixture itself. Explosive absorbers or absorbers that contain their own
oxidizer as well as catalytic absorbers are also outside the scope of this standard.
This standard specifies requirements for equipment intended for use under atmospheric
conditions.
This standard supplements and modifies the general requirements of IEC 60079-0. Where a
requirement of this standard conflicts with a requirement of IEC 60079-0, the requirement of
this standard willll take precedence.
BS EN 60079-28:2007 Referenced Document
IEC 60079 Explosive atmospheres - ALL PARTS*， 2018-01-08 Update
IEC 60079-0 Interpretation Sheet 2 - Explosive atmospheres - Part 0: Equipment - General requirements*， 2019-06-27 Update
IEC 60825-2 Corrigendum 1 - Safety of laser products - Part 2: Safety of optical fibre communication systems (OFCSs)*， 2021-06-23 Update
IEC 61508 Functional safety of electrical/electronic/programmable electronic safety-related systems – ALL PARTS together with a Commented version (see Functional Saf*， 2010-04-30 Update
IEC 61511 Functional safety - Safety instrumented systems for the process industry sector - ALL PARTS*， 2016-02-24 Update
BS EN 60079-28:2007 history
2024BS EN 60079-28:2015+A11:2024 Explosive atmospheres - Protection of equipment and transmission systems using optical radiation
2015BS EN 60079-28:2015 Explosive atmospheres. Protection of equipment and transmission systems using optical radiation
2007BS EN 60079-28:2007 Explosive atmospheres - Protection of equipment and transmission systems using optical radiation